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  1. 19 3月, 2014 7 次提交
  3. 18 3月, 2014 15 次提交
  5. 17 3月, 2014 4 次提交
  7. 16 3月, 2014 14 次提交
    • D
      drm: make minors independent of global lock · 0d639883
      由 David Herrmann 提交于 
      We used to protect minor-lookup and setup by the global drm lock. To
continue our attempts of dropping drm_global_mutex, this patch makes the
minor management independent of it. Furthermore, we make it all atomic and
switch to spin-locks instead of a mutex.

Now that minor-lookup is independent, we also move the
"drm_is_unplugged()" test into the minor-lookup path. There is no reason
to ever return a minor for unplugged objects, so keep that logic internal.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      0d639883
    • D
      drm: inline drm_minor_get_id() · 7d86cf1a
      由 David Herrmann 提交于 
      We can significantly simplify this helper by using plain multiplication.
Note that we converted the minor-type to an enum earlier so this didn't
work before.

We also fix a minor range-bug here: the limit argument of idr_alloc() is
*exclusive*, not inclusive, so we should use 64 instead of 63 as offset.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      7d86cf1a
    • D
      drm: coding-style fixes in minor handling · 1abbc437
      由 David Herrmann 提交于 
      Properly name goto-labels, remove empty lines and use DRM_ERROR if
possible.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      1abbc437
    • D
      drm: remove redundant minor->device field · 5817878c
      由 David Herrmann 提交于 
      Whenever we access minor->device, we are in a minor->kdev->...->fops
callback so the minor->kdev pointer *must* be valid. Thus, simply use
minor->kdev->devt instead of minor->device and remove the redundant field.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      5817878c
    • D
      drm: remove unneeded #ifdef CONFIG_DEBUGFS · cb0f9323
      由 David Herrmann 提交于 
      No need to check for DEBUGFS, we already have dummy-fallbacks in our
headers.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      cb0f9323
    • D
      drm: rename drm_unplug/get_minor() to drm_minor_register/unregister() · afcdbc86
      由 David Herrmann 提交于 
      drm_get_minor() no longer allocates objects, and drm_unplug_minor() is now
the exact reverse of it. Rename it to _register/unregister() so their
name actually says what they do.

Furthermore, remove the direct minor-ptr and instead pass the minor-type.
This way we know the actual slot of the minor and can reset it if
required.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      afcdbc86
    • D
      drm: move drm_put_minor() to drm_minor_free() · bd9dfa98
      由 David Herrmann 提交于 
      _put/get() are used for ref-counting, which we clearly don't do here.
Rename it to _free() and also use the common drm_minor_* prefix.
Furthermore, avoid passing the minor directly but instead use the type
like the other functions do, this allows us to reset the slot.

We also drop the redundant call to drm_unplug_minor() as drm_minor_free()
is only used from paths were that has already be called.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      bd9dfa98
    • D
      drm: allocate minors early · 05b701f6
      由 David Herrmann 提交于 
      Instead of waiting for device-registration, we now allocate minor-objects
during device allocation. The minors are not registered or assigned an ID.
This is still postponed to device-registration.

While at it, remove the superfluous output-parameter in drm_get_minor().

The reason for this early allocation is to make
dev->primary/control/render available atomically. So once the device is
alive, all of them are already set and we never have the situation where
one of them is set after another (they're either NULL or set, but never
changed). This will eventually allow us to reduce minor-ID allocation to
one base-ID instead of a single ID for each.
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      05b701f6
    • D
      drm: add minor-lookup/release helpers · 1616c525
      由 David Herrmann 提交于 
      Instead of accessing drm_minors_idr directly, this adds a small helper to
hide the internals. This will help us later to remove the drm_global_mutex
requirement for minor-lookup.

Furthermore, this also makes sure that minor->dev is always valid and
takes a reference-count to the device as long as the minor is used in an
open-file. This way, "struct file*"->private_data->dev is guaranteed to be
valid (which it has to, as we cannot reset it).
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      1616c525
    • D
      drm: provide device-refcount · 099d1c29
      由 David Herrmann 提交于 
      Lets not trick ourselves into thinking "drm_device" objects are not
ref-counted. That's just utterly stupid. We manage "drm_minor" objects on
each drm-device and each minor can have an unlimited number of open
handles. Each of these handles has the drm_minor (and thus the drm_device)
as private-data in the file-handle. Therefore, we may not destroy
"drm_device" until all these handles are closed.

It is *not* possible to reset all these pointers atomically and restrict
access to them, and this is *not* how this is done! Instead, we use
ref-counts to make sure the object is valid and not freed.

Note that we currently use "dev->open_count" for that, which is *exactly*
the same as a reference-count, just open coded. So this patch doesn't
change any semantics on DRM devices (well, this patch just introduces the
ref-count, anyway. Follow-up patches will replace open_count by it).

Also note that generic VFS revoke support could allow us to drop this
ref-count again. We could then just synchronously disable any fops->xy()
calls. However, this is not the case, yet, and no such patches are
in sight (and I seriously question the idea of dropping the ref-cnt
again).
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      099d1c29
    • D
      drm: skip redundant minor-lookup in open path · f4aede2e
      由 David Herrmann 提交于 
      The drm_open_helper() function is only used internally for drm_open() so
we can safely pass in the minor-object directly instead of the minor-id.
This way, we avoid the additional minor IDR lookup, which we already do
twice in drm_stub_open() and drm_open().
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      f4aede2e
    • D
      drm: init TTM dev_mapping in ttm_bo_device_init() · 44d847b7
      由 David Herrmann 提交于 
      With dev->anon_inode we have a global address_space ready for operation
right from the beginning. Therefore, there is no need to do a delayed
setup with TTM. Instead, set dev_mapping during initialization in
ttm_bo_device_init() and remove any "if (dev_mapping)" conditions.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      44d847b7
    • D
      drm: use anon-inode instead of relying on cdevs · 6796cb16
      由 David Herrmann 提交于 
      DRM drivers share a common address_space across all character-devices of a
single DRM device. This allows simple buffer eviction and mapping-control.
However, DRM core currently waits for the first ->open() on any char-dev
to mark the underlying inode as backing inode of the device. This delayed
initialization causes ugly conditions all over the place:
  if (dev->dev_mapping)
    do_sth();

To avoid delayed initialization and to stop reusing the inode of the
char-dev, we allocate an anonymous inode for each DRM device and reset
filp->f_mapping to it on ->open().
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      6796cb16
    • D
      drm: add pseudo filesystem for shared inodes · 31bbe16f
      由 David Herrmann 提交于 
      Our current DRM design uses a single address_space for all users of the
same DRM device. However, there is no way to create an anonymous
address_space without an underlying inode. Therefore, we wait for the
first ->open() callback on a registered char-dev and take-over the inode
of the char-dev. This worked well so far, but has several drawbacks:
 - We screw with FS internals and rely on some non-obvious invariants like
   inode->i_mapping being the same as inode->i_data for char-devs.
 - We don't have any address_space prior to the first ->open() from
   user-space. This leads to ugly fallback code and we cannot allocate
   global objects early.

As pointed out by Al-Viro, fs/anon_inode.c is *not* supposed to be used by
drivers for anonymous inode-allocation. Therefore, this patch follows the
proposed alternative solution and adds a pseudo filesystem mount-point to
DRM. We can then allocate private inodes including a private address_space
for each DRM device at initialization time.

Note that we could use:
  sysfs_get_inode(sysfs_mnt->mnt_sb, drm_device->dev->kobj.sd);
to get access to the underlying sysfs-inode of a "struct device" object.
However, most of this information is currently hidden and it's not clear
whether this address_space is suitable for driver access. Thus, unless
linux allows anonymous address_space objects or driver-core provides a
public inode per device, we're left with our own private internal mount
point.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid Herrmann <dh.herrmann@gmail.com>
      31bbe16f